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Spatial pattern recognition for near-surface high temperature increases in mountain areas using MODIS and SRTM DEM
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作者 WANG Yanxia YANG Lisha +1 位作者 HUANG Xiaoyuan ZHOU Ruliang 《Journal of Mountain Science》 SCIE CSCD 2024年第6期2025-2042,共18页
Abrupt near-surface temperature changes in mountainous areas are a special component of the mountain climate system.Fast and accurate measurements of the locations,intensity,and width of the near-surface changes are n... Abrupt near-surface temperature changes in mountainous areas are a special component of the mountain climate system.Fast and accurate measurements of the locations,intensity,and width of the near-surface changes are necessary but highly difficult due to the complicated environmental conditions and instrumental issues.This paper develops a spatial pattern recognition method to measure the near-surface high temperature increase(NSHTI),one of the lesser-attended changes.First,raster window measurement was proposed to calculate the temperature lapse rate using MODIS land surface temperature and SRTM DEM data.It fully considers the terrain heights of two neighboring cells on opposite or adjacent slopes with a moving window of 3×3 cell size.Second,a threshold selection was performed to identify the NSHTI cells using a threshold of-0.65℃/100 m.Then,the NSHTI strips were parameterized through raster vectorization and spatial analysis.Taking Yunnan,a mountainous province in southwestern China,as the study area,the results indicate that the NSHTI cells concentrate in a strip-like pattern along the mountains and valleys,and the strips are almost parallel to the altitude contours with a slight northward uplift.Also,they are located mostly at a 3/5 height of high mountains or within 400 m from the valley floors,where the controlling topographic index is the altitude of the terrain trend surface but not the absolute elevation and the topographic uplift height and cutting depth.Additionally,the NSHTI intensity varies with the geographic locations and the proportions increase with an exponential trend,and the horizontal width has a mean of about 1000 m and a maximum of over 5000 m.The result demonstrates that the proposed method can effectively recognize NSHTI boundaries over mountains,providing support for the modeling of weather and climate systems and the development of mountain resources. 展开更多
关键词 High temperature increase Mountain areas MODIS spatial pattern recognition Raster window measurement Threshold selection
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Automatic Speaker Recognition Using Mel-Frequency Cepstral Coefficients Through Machine Learning 被引量:1
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作者 U˘gur Ayvaz Hüseyin Gürüler +3 位作者 Faheem Khan Naveed Ahmed Taegkeun Whangbo Abdusalomov Akmalbek Bobomirzaevich 《Computers, Materials & Continua》 SCIE EI 2022年第6期5511-5521,共11页
Automatic speaker recognition(ASR)systems are the field of Human-machine interaction and scientists have been using feature extraction and feature matching methods to analyze and synthesize these signals.One of the mo... Automatic speaker recognition(ASR)systems are the field of Human-machine interaction and scientists have been using feature extraction and feature matching methods to analyze and synthesize these signals.One of the most commonly used methods for feature extraction is Mel Frequency Cepstral Coefficients(MFCCs).Recent researches show that MFCCs are successful in processing the voice signal with high accuracies.MFCCs represents a sequence of voice signal-specific features.This experimental analysis is proposed to distinguish Turkish speakers by extracting the MFCCs from the speech recordings.Since the human perception of sound is not linear,after the filterbank step in theMFCC method,we converted the obtained log filterbanks into decibel(dB)features-based spectrograms without applying the Discrete Cosine Transform(DCT).A new dataset was created with converted spectrogram into a 2-D array.Several learning algorithms were implementedwith a 10-fold cross-validationmethod to detect the speaker.The highest accuracy of 90.2%was achieved using Multi-layer Perceptron(MLP)with tanh activation function.The most important output of this study is the inclusion of human voice as a new feature set. 展开更多
关键词 Automatic speaker recognition human voice recognition spatial pattern recognition MFCCs SPECTROGRAM machine learning artificial intelligence
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Facial expression recognition with contextualized histograms
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作者 岳雷 沈庭芝 +2 位作者 杜部致 张超 赵三元 《Journal of Beijing Institute of Technology》 EI CAS 2015年第3期392-397,共6页
A new algorithm taking the spatial context of local features into account by utilizing contextualized histograms was proposed to recognize facial expression. The contextualized histograms were extracted fromtwo widely... A new algorithm taking the spatial context of local features into account by utilizing contextualized histograms was proposed to recognize facial expression. The contextualized histograms were extracted fromtwo widely used descriptors—the local binary pattern( LBP) and weber local descriptor( WLD). The LBP and WLD feature histograms were extracted separately fromeach facial image,and contextualized histogram was generated as feature vectors to feed the classifier. In addition,the human face was divided into sub-blocks and each sub-block was assigned different weights by their different contributions to the intensity of facial expressions to improve the recognition rate. With the support vector machine(SVM) as classifier,the experimental results on the 2D texture images fromthe 3D-BU FE dataset indicated that contextualized histograms improved facial expression recognition performance when local features were employed. 展开更多
关键词 facial expression recognition local binary pattern weber local descriptor spatial context contextualized histogram
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Rare-earth Nanoparticle-induced Cytotoxicity on Spatia Cognition Memory of Mouse Brain
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作者 Cai-Hou Lin Gui-Fen Liu +4 位作者 Jing Chen Yan Chen Ru-Hui Lin Hong-Xing He Jian-Ping Chen 《Chinese Medical Journal》 SCIE CAS CSCD 2017年第22期2720-2725,共6页
Background: Luminescent rare-earth-based nanoparticles have been increasingly used in nanomedicine due to their excellent physicochemical properties, such as biomedical imaging agents, drug carriers, and biomarkers. ... Background: Luminescent rare-earth-based nanoparticles have been increasingly used in nanomedicine due to their excellent physicochemical properties, such as biomedical imaging agents, drug carriers, and biomarkers. However, biological sat)ty of the rare-earth-based nanomedicine is of great significance for future development in practical applications. In particular, biological effects of rare-earth nanoparticles on human's central nervous system are still unclear. This study aimed to investigate the potential toxicity of rare-earth nanoparticles in nervous system function in the case of continuous exposure. Methods: Adult ICR mice were randomly divided into seven groups, including control group (receiving 0.9% normal saline) and six experimental groups ( 10 mice in each group). Luminescent rare-earth-based nanoparticles were synthesized by a reported co-precipitation method. Two different sizes of the nanoparticles were obtained, and then exposed to ICR mice through caudal vein injection at 0.5, 1.0, and 1.5 mg/kg body weight in each day for 7 days. Next, a Morris water maze test was employed to evaluate impaired behaviors of their spatial recognition memory. Finally, histopathological examination was implemented to study how the nanoparticles can affect the brain tissue of the ICR mice. Results: Two different sizes of rare-earth nanoparticles have been successfully obtained, and their physical properties including luminescence spectra and nanoparticle sizes have been characterized. In these experiments, the rare-earth nanoparticles were taken up in the mouse liver using the magnetic resonance imaging characterization. Most importantly, the experimental results of the Morris water maze tests and histopathological analysis clearly showed that rare-earth nanoparticles could induce toxicity on mouse brain and impair the behaviors of spatial recognition memory. Finally, the mechanism of adenosine triphosphate quenching by the rare-earth nanoparticles was provided to illustrate the toxicity on the mouse brain. Conclusions: This study suggested that long-term exposure of high-dose bare rare-earth nanoparticles caused an obvious damage on the spatial recognition memory in the mice. 展开更多
关键词 Mouse Brain Rare-earth Nanoparticles spatial recognition Memory
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Automatic acquisition of pattern collocations in GO 被引量:1
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作者 LIU Zhi-qing DOU Qing +1 位作者 LI Wen-hong LU Ben-jie 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2008年第1期61-67,共7页
The quality, quantity, and consistency of the knowledge used in GO-playing programs often determine their strengths, and automatic acquisition of large amounts of high-quality and consistent GO knowledge is crucial fo... The quality, quantity, and consistency of the knowledge used in GO-playing programs often determine their strengths, and automatic acquisition of large amounts of high-quality and consistent GO knowledge is crucial for successful GO playing. In a previous article of this subject, we have presented an algorithm for efficient and automatic acquisition of spatial patterns of GO as well as their frequency of occurrence from game records. In this article, we present two algorithms, one for efficient and automatic acquisition of pairs of spatial patterns that appear jointly in a local context, and the other for deter- mining whether the joint pattern appearances are of certain significance statistically and not just a coincidence. Results of the two algorithms include 1 779 966 pairs of spatial patterns acquired automatically from 16 067 game records of professsional GO players, of which about 99.8% are qualified as pattern collocations with a statistical confidence of 99.5% or higher. 展开更多
关键词 computer games automatic knowledge acquisition spatial patterns recognition pattern collocations
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Automatic pattern acquisition from game records in GO 被引量:1
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作者 LIU Zhi-qing DOU Qing 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2007年第1期100-105,共6页
关键词 computer games automatic knowledge acquisition spatial patterns recognition
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Connected Geomatics in the big data era
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作者 Deren Li Xin Shen Le Wang 《International Journal of Digital Earth》 SCIE EI 2018年第2期139-153,共15页
The development of global informatization and its integration with industrialization symbolizes that human society has entered into the big data era.This article covers seven new characteristics of Geomatics(i.e.ubiqu... The development of global informatization and its integration with industrialization symbolizes that human society has entered into the big data era.This article covers seven new characteristics of Geomatics(i.e.ubiquitous sensor,multi-dimensional dynamics,integration via networking,full automation in real time,from sensing to recognition,crowdsourcing and volunteered geographic information,and serviceoriented science),and puts forward the corresponding critical technical challenges in the construction of integrated space-air-ground geospatial networks.Through the discussions outlined in this paper,we propose a new development stage of Geomatics entitled‘Connected Geomatics,’which is defined as a multi-disciplinary science and technology that uses systematic approaches and integrates methods of spatio-temporal data acquisition,information extraction,network management,knowledge discovery,and spatial sensing and recognition,as well as intelligent location-based services pertaining to any physical objects and human activities on the earth.It is envisioned that the advancement of Geomatics will make a great contribution to human sustainable development. 展开更多
关键词 Big data GEOMATICS smart earth spatial data mining cloud computing spatial sensing and recognition
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